近年來隨著網際網路智慧型行動裝置的迅速發展，人們的生活與網路服務已經密切結合。許多網路服務(如Electronic Commerce 、Groupon…etc)可以藉由發佈/訂閱系統推廣自己的產品，並且讓人們可以自動取得自己喜愛的資訊。而發佈/訂閱系統的架構，對於使用者偏
好條件設定的描述， 常會使用特定的布林表達式(Boolean Expression model)來表達。本論文主要討論的議題為，在發佈/訂閱系統環境下，當事件發生時，如何在龐大的訂閱量中，快速且
有效率的找出匹配的訂閱者。就此，我們提出以dominance為基礎的方法，來增強資料庫查詢的效率，降低事件匹配所需的時間。
我們在研究中會根據訂閱者是屬於同質性與異質性的兩種類別分別討論其特性，這兩種類別的差異在於所有訂閱者所訂閱的屬性集合是相同或是不同。最後我們會針對我們研究的方法進行模擬，進而與現有的方法比較，證明我們的方法確實能夠有效的降低事件匹配時間。

In recent years, with the rapid development of Internet smart mobile devices, people's lives, and Internet services have been closely integrated. Many web services (such as Electronic Commerce, Groupon ... etc) can promote their products through the publish /subscribe system and allow people to automatically get their favorite information. The architecture of the publish /subscribe system, which describes the user preference conditions, is expressed using a specific Boolean expression model. The main topic of this paper is to discuss how to find out the matching subscribers quickly and efficiently in the large data volume in the publish/subscribe system environment when the event occurs. Therefore, we propose a dominance-based approach to enhance database query efficiency and reduce event matching time.
In this study, we discuss the advantages and disadvantages of the two types of subscribers, which are homogeneous and heterogeneous. The difference between the two categories is that all the subscribers subscribe to the same or different set of attributes. Lastly, we will simulate with our method, and compared with the existing methods, we prove that our method can effectively reduce the event matching time.

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